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A novel role for connexin hemichannel in oxidative stress and smoking-induced cell injury.

ABSTRACT: Oxidative stress is linked to many pathological conditions, including ischemia, atherosclerosis and neurodegenerative disorders. The molecular mechanisms of oxidative stress induced pathophysiology and cell death are currently poorly understood. Our present work demonstrates that oxidative stress induced by reactive oxygen species and cigarette smoke extract depolarize the cell membrane and open connexin hemichannels. Under oxidative stress, connexin expression and connexin silencing resulted in increased and reduced cell deaths, respectively. Morphological and live/dead assays indicate that cell death is likely through apoptosis. Our studies provide new insights into the mechanistic role of hemichannels in oxidative stress induced cell injury.

SUBMITTER: Ramachandran S

PROVIDER: S-EPMC1933596 | biostudies-literature | 2007 Aug

REPOSITORIES: biostudies-literature

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A novel role for connexin hemichannel in oxidative stress and smoking-induced cell injury.

Ramachandran Srinivasan S Xie Lai-Hua LH John Scott A SA Subramaniam Shankar S Lal Ratnesh R

PloS one 20070808 8

Oxidative stress is linked to many pathological conditions, including ischemia, atherosclerosis and neurodegenerative disorders. The molecular mechanisms of oxidative stress induced pathophysiology and cell death are currently poorly understood. Our present work demonstrates that oxidative stress induced by reactive oxygen species and cigarette smoke extract depolarize the cell membrane and open connexin hemichannels. Under oxidative stress, connexin expression and connexin silencing resulted in ...[more]

PMID: 17684558

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